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991.
《Journal of the European Ceramic Society》2022,42(8):3559-3569
To explore the mechanism of phase transformation, YTa3O9 was prepared by an integrated one-step synthesis and sintering method at 1500 °C using Y2O3 and Ta2O5 powders as starting materials. High-temperature XRD patterns and Raman spectra showed that a phase transformation from orthorhombic to tetragonal took place in YTa3O9 through the bond length and angle changes at 300–400 °C, which caused a thermal conductivity rise. To inhibit the phase transformation, a high-entropy (Y0.2La0.2Ce0.2Nd0.2Gd0.2)Ta3O9 (HE RETa3O9) was designed and synthesized at 1550 °C using the integrated solid-state synthesis and sintering method. In tetragonal structured HE RETa3O9, phase transformation was inhibited by the high-entropy effect. Furthermore, HE RETa3O9 exhibited low thermal conductivity, and its tendency to increase with temperature was alleviated (1.69 W/m·K, 1073 K). Good phase stability, low thermal conductivity and comparable fracture toughness to YSZ make HE RETa3O9 promising as a new thermal barrier coating material. 相似文献
992.
Gehad Abo-Lila Taha Sokkar Eman Seisa Emam Omar 《Microscopy research and technique》2022,85(2):667-684
In this article, an adaptive denoising method is suggested to accurate investigate the optical and structural features of polymeric fibers from noisy phase shifting microinterferograms. The mixed class of noise that may produce in the phase-shifting interferometric techniques is established. To our knowledge, this is an early study considered the mixing noises that may occur in microinterferograms. The suggested method utilized the convolution neural networks to detect the noise class and then denoising, it according to its class. Four convolution neural networks (Googlenet, VGG-19, Alexnet, and Alexnet–SVM) are refined to perform the automatic classification process for the noise class in the established data set. The network with the highest validation and testing accuracy of these networks is considered to apply the suggested method on realistic noisy microinterferograms for polymeric fibers, polypropylene and antimicrobial polyethylene terephthalate)/titanium dioxide, recoded using interference microscope. Also, the suggested method is applied on noisy microinterferograms include crazing and nanocomposite material. The demodulated phase maps and the three-dimensional birefringence profiles are calculated for tested fibers according to the suggested method. The obtained results are compared with the published data for these fibers and found to be in good agreements. 相似文献
993.
《International Journal of Hydrogen Energy》2022,47(10):6911-6923
A FeCoCrMoSi amorphous coating (AC) was fabricated on Ti6Al4V alloy (TA) by subsonic flame spraying (SFS) technique, which was used to improve its corrosion resistance. The morphology, element distribution and chemical composition of obtained coating were analyzed using a scanning electron microscope (SEM), energy dispersive spectroscopy (EDS) and X–ray Fluorescence (XRF), respectively, and its amorphous structure was confirmed by X–ray diffraction (XRD). The immersion corrosion behavior and electrochemical performance of FeCoCrMoSi AC immersed in 3.5% NaCl solution for the different days were systematically investigated, and the corrosion mechanism of amorphous structure was also discussed by the model of passive film. The results show that the FeCoCrMoSi AC exhibits the dense amorphous structure, which is beneficial to improving the anti–corrosion performance of TA. The potentiodynamic polarization curve (PPC) and electrochemical impedance spectroscopy (EIS) indicate that the FeCoCrMoSi AC with the lowest icorr of 1.479 × 10?6 A·cm?2 immersed for 60 days has the largest capacitor loop diameter of 7.53 × 105 and charge transfer resistance Rct of 4.31 × 104 Ω, showing the highest comprehensive corrosion resistance. The mechanism of corrosion resistance is contributed to the Cr–rich passive film, which is further stabilized by the addition of Mo. 相似文献
994.
《International Journal of Hydrogen Energy》2022,47(1):57-68
Three different proton conducting polymeric membrane materials (Nafion® 115, Nafion® 212, and sulfonated Diels-Alder polyphenylene [SDAPP]) were evaluated for use in SO2-depolarized electrolyzers for the production of hydrogen via the hybrid sulfur cycle. Their performance was measured using different water feed strategies to minimize overpotential losses while maintaining high product acid concentration. Both thin membranes (Nafion® 212 and SDAPP) showed performance superior to that of the thicker Nafion® 115. The SDAPP membrane electrode assembly (MEA) performed well at higher acid concentrations, maintaining low ohmic and kinetic overpotentials. Finally, short-term (100-h) stability tests under constant current conditions showed minimal degradation for the SDAPP and Nafion® 212 MEAs. SDAPP MEA performance approached the targets needed to make the hybrid sulfur cycle a competitive process for hydrogen production (product acid concentration ≥65 wt% H2SO4 at ≤ 0.6-V cell potential and ≥0.5 A-cm?2 current density). 相似文献
995.
《International Journal of Hydrogen Energy》2022,47(2):962-970
Ce-based organic framework materials [UIO-66(Ce)] were prepared, and the UIO-66(Ce)/ZnCdS composite was attained by microwave irradiation. Moreover, the photocatalytic hydrogen production activity was evaluated. The experimental results revealed that the ZnCdS nanoparticle was decorated on the surface of UIO-66(Ce), and the hydrogen production ability of ZnCdS nanoparticle was improved by UIO-66(Ce) significantly. The hydrogen production yield of UIO-66(Ce)/ZnCdS reaches 3.958 mmol/g·h, in which is as about 1.95 times as that of ZnCdS (2.031 mmol/g·h). The improvement for photocatalytic hydrogen production yield is because UIO-66(Ce) can facilitate the photoinduced carriers to separating. 相似文献
996.
Bisphosphonates (BPs)-associated atypical femoral fractures (AFFs) present with impaired fracture healing, yet the underlying mechanism is unclear, which prevents the development of effective therapy. Peripheral sensory nerve has been shown to regulate fracture healing via releasing neuropeptides. Here we show that long-term BPs pre-treatment leads to fracture non-union in rats, characterized by reduced expression of calcitonin gene-related peptide (CGRP, a predominant type of neuropeptides) and abundant fibrous tissues in the non-bridged fracture gap, mimicking clinical AFFs. By using single-cell RNA-sequencing, long-term BPs treatment was identified to promote transition of progenitor cells into a specific cluster of fibroblasts that actively deposit dense extracellular matrix (ECM) to prevent fracture callus bridging. Administration of exogenous CGRP at early stages of fracture repair, in contrast, eliminates the ECM-secreting fibroblast cluster, attenuates fibrogenesis, and facilitates callus bridging, suggesting CGRP is a promising agent to facilitate AFF healing. Accordingly, we have developed an innovative magnesium (Mg) containing hybrid intramedullary nail fixation system (Mg-IMN) to effectively rescue BPs-impaired fracture healing via elevating CGRP synthesis and release. Such device optimizes the fracture healing in BPs-pretreated rats, comparable to direct administration of CGRP. These findings address the indispensable role of CGRP in advancing the healing of AFFs and develop translational strategies to accelerate AFF healing by taking advantage of the CGRP-stimulating effect of Mg-based biodegradable orthopedic implant. The study also indicates fibrosis could be targeted by augmenting CGRP expression to accelerate fracture healing even under challenging scenarios where fibroblasts are aberrantly activated. 相似文献
997.
《International Journal of Hydrogen Energy》2022,47(98):41640-41647
Two-dimensional (2D) materials have been widely developed due to their attractive properties. Here, by using density functional theory (DFT) calculations, for the first time, we explore potential applications of the novel XIS (X = Al, Ga, In) monolayer 2D materials on photocatalytic water splitting. A series of simulations were carried out to predict and study the structural, elastic, phononic, optical and electronic properties of 2D XIS materials. The results show that GaIS and InIS demonstrate low thermal conductivity. For optical properties, AlIS shows strong light absorption coefficients and refractive index only under ultraviolet (UV) light, while GaIS and InIS show stronger performance under both visible light and UV light with the band edge positions spanned the redox potential of water. The reasonable band positions and bandgaps make them promising photocatalysts for water splitting. This work reveals the potential applications of monolayer 2D XIS in thermal, electronic, and photocatalytic water splitting. 相似文献
998.
Arzu Karataş 《International Journal of Food Science & Technology》2022,57(3):1429-1439
The use of agro-industrial waste as substrates for mushroom cultivation is considered a promising management strategy for reducing and valorising these wastes, simultaneously reducing the cost of mushroom cultivation. In this study, oyster mushroom Pleurotus ostreatus were cultivated on twelve substrates composed of either tea waste, lime sawdust, alder sawdust, hornbeam sawdust/shaving, wheat stalk-straw, wheat bran or their composite to determine the proximate composition and accumulation of thirteen elements in their fruiting bodies. The proximate composition of P. ostreatus did not show a significant difference, regardless of the employed substrate. (one-way manova ; F(66, 107) = 1.329, Wilk’s λ = 0.041, P > 0.05). However, their chemical element contents show a statistically significant difference (one-way manova ; F(132, 418) = 32.163, Wilk’s λ = 0.000, P < 0.05). These results were supported by discriminant function and principal component analyses. The highest mean concentrations of six of twelve elements (i.e., Ca, Mg, Na, Zn, Cd and Cr) were recorded in P. ostreatus cultivated on the lime-sawdust substrate. Three health indices viz., estimated daily intake, target hazard quotient (THQ) and total THQ were applied to determine the risk to human health via the consumption of P. ostreatus, suggesting that they are safe for human consumption. 相似文献
999.
Hai Chi Yujie Li Guoqin Liu 《International Journal of Food Science & Technology》2022,57(8):5376-5387
In this study, a new electrochemical strategy based on the fabrication of a molecularly imprinted sensor onto a MoS2-loaded peanut shell carbon complex with gold nanoparticles (AuNPs) and nitrogen-doped carbon dots (N-CDs) was proposed for the detection of benzo(a)pyrene (BaP). Molecularly imprinted polymer (MIP) films were prepared by cyclic voltammetry (CV) using 2-mercaptobenzimidazole (2-MBI) as a functional monomer in the presence of BaP. The surface morphologies, structural characteristics and electrochemical properties of the obtained MIP/AuNPs/N-CDs/PSBC/MoS2/GCE were investigated via scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive spectrometry (EDS), Fourier transform infrared spectrometry (FTIR), X-ray diffraction (XRD), UV–Vis spectrometry, fluorescence spectrometry, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Under the optimised conditions, the detection range of the electrode towards BaP varied from 5 nM to 20 μM with a detection limit of 1.5 nM. The prepared electrochemical sensor also exhibited good stability, relevant reproducibility and high selectivity. The application of the sensor in the actual analysis of edible oil samples showed promising results, thereby being relevant as a biomimetic sensing platform for the detection of chemical hazards in food and environment. 相似文献
1000.
Xiehuan Li Dan Ye 《International Journal of Adaptive Control and Signal Processing》2022,36(1):104-121
In this article, the memory-based dynamic event-triggered controller design issue is investigated for networked interval type-2 (IT2) fuzzy systems under non-periodic denial-of-service (DoS) attacks. For saving limited network bandwidth, a novel memory-based dynamic event-triggered mechanism (DETM) is proposed to schedule data communication. Unlike existing event-triggered generators, the developed memory-based DETM can utilize a series of newly released signals and further save network resources by introducing interval dynamic variables. Moreover, to improve design flexibility, an IT2 fuzzy controller with freely selectable fuzzy rule number and premise membership functions (MFs) is synthesized. Then, a new switched time-delay system with imperfectly matched MFs is established under the consideration of memory-based DETM and DoS attacks simultaneously. Besides, based on the property of MFs, the boundary information of membership grades and slack matrices are introduced in the stability analysis. Furthermore, by using a piecewise Lyapunov–Krasovskii method, membership-functions-dependent criteria are deduced to ensure the asymptotic stability of built fuzzy switched systems. Finally, the effectiveness of proposed control strategies is demonstrated by simulation examples. 相似文献